<!DOCTYPE html>
<html lang="zn">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>toString</title>
    <script>
        function Person(name,age,gender){
            this.name = name;
            this.age = age;
            this.gender = gender;
        }

        // 修改person原型的toString
        Person.prototype.toString = function(){
            return "Person[name="+this.name+",age="+this.age+",gender="+this.gender+"]";
        };

        // 创建Person实例
        var per = new Person("孙悟空",18,"男");
        var per2 = new Person("猪八戒",28,"男");

        // 当我们直接在页面中打印一个对象时，实际上是输出对象的toString()方法的返回值
        // 如果我们希望在输出对象时不输出[object Object]可以为对象添加一个toString()方法

        console.log(per.toString());
        console.log(per);
        console.log(per.__proto__.__proto__.hasOwnProperty("toString"));
    </script>
</head>
<body>
    
</body>
</html>